in Environmental management and sustainable development (2014), 3(2), 138-153

The effects of urban sprawl have been well documented, particularly regarding energy consumption. Suburban neighbourhoods are known to be energy inefficient and urban sprawl is considered as a major issue ... [more ▼]

The effects of urban sprawl have been well documented, particularly regarding energy consumption. Suburban neighbourhoods are known to be energy inefficient and urban sprawl is considered as a major issue for sustainable development. To improve the energy efficiency of existing suburban urban fabrics is a major challenge that must be addressed to favour a sustainability transition of our built environment. In this context, this paper aims at investigating several scenarios that could be developed to improve the sustainability of existing suburban neighbourhoods: three main types of scenarios (building insulation, density, and urban form) and twelve sub-scenarios, which are focused on the possible evolution of the existing suburban building stocks, are proposed. Quantitative methods developed in previous research are used to assess and compare building and transportation energy consumption of a representative suburban case study. This application aims at investigating two main research questions: (1) "how to intervene in suburban neighbourhoods?" and (2) «where to intervene?" The main results of this application, which are focused on energy efficiency, are then studied in a larger framework to highlight their opportunities and constraints. The main findings of the paper are that, beyond the traditional polarisation of the debates on the energy efficiency of our built environment between the “compact” and the “sprawled” city, a new pragmatic paradigm, which is focused on the smooth densification of existing suburban neighbourhoods, can make them evolve towards greater sustainability. [less ▲]

There is an urgent need to reduce energy uses in new and retrofitted buildings. In Europe, energy consumption in the building sector still represents more than 40% of the final energy use. Emerging ... [more ▼]

There is an urgent need to reduce energy uses in new and retrofitted buildings. In Europe, energy consumption in the building sector still represents more than 40% of the final energy use. Emerging countries are also concerned by such issues at even wider levels because of the huge demographic growth they are witnessing. Numerous research studies have highlighted the need to produce more efficient buildings, but also to retrofit the existing building stock. However, research methods and tools that allow a precise quantification of energy uses in buildings and energy savings related to various actions (insulating the roofs, changing the glazing, behavioral changes, etc.) are mainly dedicated to trained professional users, thus neglecting the huge potential energy savings that is linked to individual actions undertaken by citizens in their dwellings. In this context, the main aim of our research is to raise awareness of energy efficiency in residential buildings and encourage positive changes to the energy efficiency of the building stock, starting at the individual scale. This paper first presents the methodology that allows a precise energy assessment (heating, cooling, ventilation, lighting, appliances and cooking) of buildings (at the house, neighborhood, city and region scales) on the basis of a “bottom-up” approach. This methodology uses a typological classification of buildings, thermal simulations and local surveys. In this paper, this methodology is applied to the Walloon (Belgium) building stock. Many parameters are defined and taken into account to capture the specificities of numerous types of buildings (e.g., the number of floors, common ownership, orientation, thermal performances, ventilation, etc.). Several occupation modes are modelled to capture the impact of occupants’ behavior on energy consumption. To take into account the impact of urban form, correction factors are defined and applied according to the type of neighborhoods in which the buildings are located. All things considered, 250,000 individual results are obtained and stored in a huge database. Linear extrapolations and correction factors are used to extrapolate and apply these results to any type of residential building in Wallonia. This methodology is then used to develop an online portal that aims to strengthen citizens’ awareness of the necessity for ecological changes in the building sector and encourage individual actions to improve the energy efficiency of buildings. This tool allows for a transfer of the main results of a two-year scientific research effort to citizens in a very simple and intuitive way. Although the results presented in this paper are focused on Wallonia (Belgium), the research is easily reproducible to other territories by adapting local parameters. [less ▲]

This paper presents a practical handbook that aims at helping local authorities and private developers to build and assess “sustainable neighbourhoods” in Wallonia (Belgium). This handbook was developed ... [more ▼]

This paper presents a practical handbook that aims at helping local authorities and private developers to build and assess “sustainable neighbourhoods” in Wallonia (Belgium). This handbook was developed by the Research Centre on Territorial, Urban and Rural Sciences (Lepur, University of Liège), at the request of the Walloon Minister of the Environment, Spatial Planning and Mobility. The concrete aim of the handbook is to concretely define the concept of "sustainable neighbourhood" by clearly tagging the minimum criteria that a real estate project must meet to obtain the “sustainable neighbourhood” label in Wallonia. It is a tool for decision support in the design as well as the evaluation of real estate projects, since the early stages of their design. The handbook is structured into 5 main theme and 25 criteria of sustainability. In a broad vision of sustainability, this handbook is not strictly limited to energy issues but considers "sustainability" in all its multiple components: location, network connection, mobility of inhabitants, use of natural resources, landscaping, waste management, diversity of function, social interactions, among others. The handbook is firstly presented and, then, applied to 12 recent case studies in order to identify common invariants in the design process of “sustainable neighbourhoods” and barriers to the integration of cross-cutting principles of sustainability in neighbourhood projects. Our main results namely show that the criteria dealing with energy performance of buildings and green spaces have percolated in many cases. However, the diversity of housing types, the accessibility to handicapped peoples, social diversity and participation issues remain poorly addressed in most of the cases studies. [less ▲]

Zero-energy buildings (ZEBs) are attracting increasing interest internationally in policies aiming at a more sustainably built environment, the scientific literature and practical applications. Although ... [more ▼]

Zero-energy buildings (ZEBs) are attracting increasing interest internationally in policies aiming at a more sustainably built environment, the scientific literature and practical applications. Although “zero energy” can be considered at different scales (e.g., community, city), the most common approach adopts only the perspective of the individual building. Moreover, the feasibility of this objective is not really addressed, especially as far as the retrofitting of the existing building stock is concerned. Therefore, this paper aims first to investigate the opportunity to extend the “zero-energy building” concept to the neighbourhood scale by taking into account two main challenges: (1) the impact of urban form on energy needs and the on-site production of renewable energy and (2) the impact of location on transportation energy consumption. It proposes a simplified framework and a calculation method that is then applied to two representative case studies (one urban neighbourhood and one rural neighbourhood) to investigate the feasibility of zero-energy in existing neighbourhoods. The main parameters that act upon the energy balance are identified. The potential of “energy mutualisation” at the neighbourhood scale is highlighted. This paper thereby shows the potentialities of an integrated approach linking transportation and building energy consumptions. [less ▲]

Improving energy efficiency in the building and transportation sectors is a viable approach to mitigate the effects of climate change and has become an important policy target. As a result, in addition to ... [more ▼]

Improving energy efficiency in the building and transportation sectors is a viable approach to mitigate the effects of climate change and has become an important policy target. As a result, in addition to scientific research and public policies addressing energy efficiency, raising public awareness of the impact of the behaviour of citizens to energy efficiency is crucial and could quickly lead to significant reductions in the total energy consumption of a territory. In this context, this paper presents a new online interactive tool that enables not only citizens but also local authorities and private developers to (1) assess the sources of energy consumption related to housing and to daily mobility at both the individual and neighbourhood scales, (2) compare these sources and (3) determine relevant and personalised suggestions to reduce energy consumption. Numerous methods and tools, including a typological classification of buildings, thermal dynamic simulations, life-cycle assessments and statistical treatments of national censuses, were used to produce the two large databases used in this interactive tool. This report represents the primary results of a three-year long scientific research project dedicated to the study of energy efficiency in buildings and for daily mobility that is accessible to a large non-specialised audience. [less ▲]

in Single Family Housing Estates of the Post - War Era – a European Comparison of Opportunities and Risks. (2014)

This paper addresses the challenges and conditions of a sustainability transition of suburban areas in Wallonia (Belgium), articulated around energy efficiency in the building and in the transportation ... [more ▼]

This paper addresses the challenges and conditions of a sustainability transition of suburban areas in Wallonia (Belgium), articulated around energy efficiency in the building and in the transportation sectors. Three scenarios focused on the evolution of the existing building stock are modelled and assessed (the insulation of buildings, an increase in the built density and demolition / reconstruction). Our main findings show that, beyond the traditional polarization of the debates on energy efficiency of our built environment between the “compact city” and the “sprawled city”, a new pragmatic paradigm, focused on the transition of suburban areas by “densification”, can make suburban areas evolve towards more sustainability. However, these main results focused on energy efficiency need to be studied in a larger framework to concretely operationalize a suburban sustainability transition. In this perspective, concrete prospects for a further research project on “suburban densification” are proposed. There address the opportunities for transnational cooperation as well as the proposition of potential research activities. [less ▲]

This paper analyses the impact of territorial structures upon energy consumption in the Walloon Region (Belgium). The rationale for this research is to consider the long-term influence of spatial planning ... [more ▼]

This paper analyses the impact of territorial structures upon energy consumption in the Walloon Region (Belgium). The rationale for this research is to consider the long-term influence of spatial planning decisions upon energy consumption in both residential building stock and home-to-work commuting. The analysis has been conducted on a regional scale (16,844 km2) and includes urban, peri-urban and rural settlements. Those settlements that perform well in mobility also appear to perform well in terms of building energy consumption. Even though this is not generally the case, it further reveals that some rural settlements characterized by low density show good performance in terms of energy efficiency. This permits a much more progressive approach in terms of spatial planning, whereby compact cities may be viewed as part of the solution, albeit not the whole solution. [less ▲]

This paper addresses the challenges, transformations and conditions of a sustainable suburban transition in Wallonia (Belgium). Two powerful levers are used: (1) urban form, which is considered in ... [more ▼]

This paper addresses the challenges, transformations and conditions of a sustainable suburban transition in Wallonia (Belgium). Two powerful levers are used: (1) urban form, which is considered in addition to the individual building scale, and (2) mobility, because sprawl spatially separates activities, resulting in an increase in travel distances and energy used in transportation. Three scenarios focused on the evolution of the existing building stock are modelled and assessed (the retrofitting of existing neighbourhoods, an increase in the built density and demolition / reconstruction) to answer two main questions: "how to intervene in suburban areas?" and" where to intervene? ". [less ▲]

Zero-Energy” Building (ZEB) is arousing more and more interest internationally, both in policies aiming at a more sustainable built environment (such as the European Directive PEB that will require, for ... [more ▼]

Zero-Energy” Building (ZEB) is arousing more and more interest internationally, both in policies aiming at a more sustainable built environment (such as the European Directive PEB that will require, for example, all new buildings to be “nearly Zero-Energy” Buildings (nZEB) by 2020) and in the scientific literature. Although Zero-Energy can be considered at different scales, this approach only adopts the perspective of the individual building and neglects phenomena linked to larger scales. Therefore, this paper aims at investigating the “Zero-Energy Neighbourhood” concept. It proposes a calculation method that takes into account three main topics: the energy consumption of buildings, the impact of the location on the energy consumption for daily mobility and the use of renewable energies. An application of this calculation method to two representative case studies (one urban neighbourhood and one suburban neighbourhood) is proposed. Main parameters that act upon the energy balance are highlighted and combined to propose concrete results to improve our built environment and move towards more sustainability. Hourly and monthly balances, the potential of “energy mutualisation” and smart grids are keys challenges that are of crucial importance in the scope of a Zero-Energy objective at the neighbourhood scale. [less ▲]